In a conventional waterproof push button switch of this type, a plurality of terminal portions protruding from the bottom portion of the switch are soldered and then electrically connected to a circuit pattern of a circuit substrate after having been passed through through-holes of the circuit substrate. On a surface of the circuit substrate, other electronic components are also mounted. When water adheres to a connected portion between the circuit substrate and the waterproof push button switch or other electronic components, a short-circuit accident or the like may occur. Thus, the substrate surface of the circuit substrate is covered with a resin in order to provide waterproofing to the connected portion. Waterproofing is thereby achieved. A case for the switch may comprise divided parts and have a connection formed between divided parts at a position midway in a direction of height or a height direction of the case. Accordingly, water may enter through the connection formed between the divided parts as well. The waterproof push button switch is therefore covered with the resin to a height at which the connection formed between the divided parts of the case is hidden by the resin, as disclosed in Japanese Patent Publication No. 2005-197045 FIG. 4